ARM VERSION 1.2 User Manual
Vector Floating-point Programming
ARM DUI 0068B
Copyright © 2000, 2001 ARM Limited. All rights reserved.
6-33
6.7.14
FMRX, FMXR, and FMSTAT
Transfer contents between an ARM register and a VFP system register.
Syntax
FMRX{cond} Rd, VFPsysreg
FMXR{cond} VFPsysreg, Rd
FMSTAT{cond}
where:
cond
is an optional condition code (see VFP and condition codes on page 6-8).
VFPsysreg
is the VFP system register, usually
FPSCR
,
FPSID
, or
FPEXC
(see
Rd
is the ARM register.
Usage
The
FMRX
instruction transfers the contents of
VFPsysreg
into
Rd
.
The
FMXR
instruction transfers the contents of
Rd
into
VFPsysreg
.
The
FMSTAT
instruction is a synonym for
FMRX r15, FPSCR
. It transfers the floating-point
condition flags to the corresponding flags in the ARM CPSR (see VFP and condition
codes on page 6-8).
codes on page 6-8).
Note
These instructions stall the ARM until all current VFP operations complete.
Exceptions
These instructions do not produce any exceptions.
Examples
FMSTAT
FMSTATNE
FMXR FPSCR, r2
FMRX r3, FPSID
FMSTATNE
FMXR FPSCR, r2
FMRX r3, FPSID